Alert archive / Montana / Mesoscale Discussions in 2015

Mesoscale Discussion 859

June 1, 201519 counties in Montana; Park County, Wyoming

The Storm Prediction Center issued this mesoscale discussion at Jun 1, 2015, 4:31 PM MDT for 19 counties in Montana; Park County, Wyoming. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued: Jun 1, 2015, 4:31 PM MDT (22:31 UTC)
Expired: Jun 1, 2015, 5:30 PM MDT
In force: 59 min
Issued by: the Storm Prediction Center

Counties Beaverhead County, MT, Broadwater County, MT, Carbon County, MT, Cascade County, MT, Fergus County, MT, Gallatin County, MT, Golden Valley County, MT, Jefferson County, MT, Judith Basin County, MT, Madison County, MT, Meagher County, MT, Musselshell County, MT, Park County, MT, Petroleum County, MT, Silver Bow County, MT, Stillwater County, MT, Sweet Grass County, MT, Wheatland County, MT, Yellowstone County, MT, Park County, WY

The radar

The Billings radar (KBLX), 150 km from the middle of the area, began a volume at 22:33 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 10.5 hours before the alert went out and 205 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 43 J/kg
Mixed-layer CIN: -204 J/kg
Mixed-layer LCL: 1644 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 102 m²/s²
0-3 km storm-relative helicity: 67 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 1, 12:48 PM MDT	Mesoscale Discussion	SPC	Beaverhead, Gallatin, Madison, Park	117 min
Jun 1, 1:46 PM MDT	Mesoscale Discussion	SPC	Broadwater, Carbon, Cascade, Fergus, Gallatin, Golden Valley and 13 more	89 min
Jun 1, 2:19 PM MDT	Severe Thunderstorm Watch	SPC	Beaverhead, Broadwater, Carbon, Cascade, Fergus, Gallatin and 14 more	7 hr
Jun 1, 2:41 PM MDT	Mesoscale Discussion	SPC	Fallon, Wibaux	2 hr

Nearby

Mesoscale Discussions in Montana, 2015 Mesoscale Discussions in Wyoming, 2015 Every mesoscale discussion in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.